1. Field of the Invention
This invention relates to a new method of producing aggregate products using glass.
2. Description of Related Art
Various states have instituted regulations requiring the diversion of a certain percentage of the waste stream from landfills. For example, in 1989 the California Integrated Waste Management Board (xe2x80x9cCIWMBxe2x80x9d) adopted Assembly Bill AB939 which required a fifty percent diversion of the waste stream from landfills by the year 2000. Cities throughout California continue to struggle to meet the AB939 requirements to avoid penalties as high as $10,000 per day if the requirements are not met.
Various entities including Raisch Products began to analyze the waste stream to determine what materials in the waste stream could be recycled, or recycled to a greater extent, and thus diverted from landfills. Waste glass proved to be one such material. Because it was known that glass has been used in the manufacture of hot asphalt, Raisch Products decided to experiment with recycled glass in forming aggregate suitable for road base use.
Various states have regulations specifying requirements for such aggregates used for road construction. For example, the State of California Department of Transportation (xe2x80x9cCALTRANSxe2x80x9d) Class 2 aggregate is a specification generated by California""s highway department used for road construction. Such material is conventionally composed of recycled asphalt and concrete. CALTRANS recently addressed the use of recycled glass by revising the Class 2 aggregate specification to include reclaimed asphalt concrete, Portland cement concrete, lean concrete base, cement treated base, glass or a combination of any of these materials.
As noted above, Raisch Products experimented with the use of recycled glass in forming aggregate suitable for road base. In particular, Raisch Products began experimenting by producing CALTRANS Class 2 aggregate using recycled glass. However, Raisch Products found that the recycled glass merely increased the cost of Class 2 aggregate production without any added any benefit other than diverting a portion of the waste stream from landfills.
Base rock which is mined from local quarries is often suitable for replacing the finer aggregate materials which are used in making lesser quality aggregates, for example, such as aggregates which conform with the City of San Jose""s Class 3 aggregate requirements. Such aggregates conforming with City Class 3 requirements are a lesser quality than the aggregates which conform to the City of San Jose""s Class 2 requirements and/or the State of California""s CALTRANS Class 2 requirements. In fact, aggregates which conform with City Class 3 requirements often do not to meet the specifications on many State of California road construction jobs which specify the City Class 2 or the CALTRANS Class 2 requirements. In fact, it is often necessary to treat locally mined base rock with quicklime to achieve even a City Class 3 specification.
An object of the present invention is to provide a method of producing new and improved higher quality aggregate products using lower quality initial aggregate materials and crushed glass.
Another object of the present invention is to provide a method of producing aggregate products which diverts a portion of the waste stream from landfills.
Yet another object of the present invention is to provide a method of producing aggregate products using recycled glass in order to use less native materials and thus save natural resources.
A further object of the present invention is to provide a method of producing a higher quality aggregate product using an initial aggregate material that is conventionally used for producing lower quality aggregate products and using glass which is conventionally part of the waste stream which is directed into landfills.
In summary, one aspect of the present invention is directed to a method of producing an aggregate product including the steps of providing an initial aggregate material having an R-value of less than approximately 75 MIN, which does not conform with higher aggregate quality requirements, and introducing a percentage weight of crushed glass material into the initial aggregate and mixing it therewith to form the aggregate product which has an R-value greater than approximately 78 MIN.
Another aspect of the present invention is directed to a method of producing an aggregate product including the steps of providing an initial aggregate material and introducing a percentage weight of crushed glass material into the initial aggregate material to form the aggregate product. The initial aggregate material and the aggregate product conform with following aggregate grading and quality specifications:
The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.